The present invention relates generally to filter apparatus, and more specifically relates to filter apparatus containing filter members adapted to be adjustably securable within a housing to facilitate optimal removal and interchangeability of filter elements.
Many filter apparatus, particularly of those designed for use in industrial applications, include a conduit or housing and a rigid or semi-rigid filter element contained therein. As an example, many of these filter elements are of a generally cylindrical form and have an inlet end into which the fluid flows. Filtering occurs when the fluid flow passes through the radial surfaces of the filter element. It will be appreciated that the restriction of the filter element creates a pressure differential across the filter element which the element must withstand. It will further be appreciated that this pressure differential may take on significant proportions, particularly in high flow rate or high fluid pressure environments. Therefore, it is preferable to utilize a filter element which is of suitable construction to withstand high differential pressures and which is suitably supportable within the filter housing so as to provide optimal filter element durability and reliability.
In many applications, and particularly in industrial applications, it is not uncommon to encounter difficulty in manufacturing filter components within close tolerances such that parts are easily interchangeable. This is particularly true with respect to filter elements which tend to be of materials which are less rigid and much more difficult to form than machinable parts. Filter elements are typically expected to be removed at periodic intervals for servicing or replacement. At these times, it is often desirable that the filter element be quickly removable to minimize down time of the fluid system. Further, it is often preferable that the filter element be replacable with another element. Because of the difficulty in exact dimensional duplication discussed above, to accomplish this end, prior art methods have typically relied upon either spring mechanisms or boltably adjustable mechanisms to support the filter element, such mechanisms typically located at one end of the filter element. Spring mechanisms have an inherent drawback in that they, by design, have a resiliency which; (a) places a compression load on a filter element when it is in an unpressured state and, (b) will yield when fluid pressure builds to a threshold level and thereby cease to properly support the filter element. Boltably adjustable mechanisms as found in the prior art are not only typically troublesome and time-consuming to adjust, often requiring multiple "trial and error" fittings, but also are often impractical in many environments such as in filter apparatus used in systems containing corrosive fluids.
Accordingly, the present invention provides a method and apparatus wherein a filter element is relatively easily removable from a filter apparatus and is adjustable for variations in filter element construction tolerances, which provides a solid support for the filter member, and which is suitable for use in corrosive environments.